Primer.



D. F. ASBURY.

PRIMER. APPL.\.AT10N men uLY I3. m.

1,1 86,264 luten'fd Jurw 19M.

UNTTED STATES PATENT OFFICE.

DORSEY FROST ASBURY. OF

WASHINGTON. DISTRICT OF COLUMBIA. ASSIGNOR TO UNITED STATES ORDNANCE COMPANY. OF WASHINGTON. PISTRICT OF COLUMBIA, A CORPORATION OF VIRGINIA.

PRIMER.

1.186.264. Specification 0f Letters Patent Patented Julie 6, 1916.

Application led July 13. 1915. Serial NoA 39.593.

e it linown that l` l)oi:si:v F. .\sninv. a eitizen ot' the i'nited States. and resident of the eit'v of \\'ashington. in the listiiet of (ioluiiihia. have invented eertain new and useful Improvements in lriniers. ot' whieh the following is a speeitieation.

.\l invention relates to primers and more paitieiilarlv to plungers therefor.

In the eonstruetion of primers of the tvpe used l'or igniting the ehaige in guns of largo ealiher there is einhodied a plunger whieh is normall v held in sa t'e position with respect to the pereussion rap liv a shearing thinge l'ziriiied integral therewith and alilittilig a shoulder formed on the plunger eup. ln order to assure hotli the safety and eorieet operation ot the primer this shearing flange must possess a iiredetermined thiehness. lf' this flange has less than the requisite thiekness it will he slieared as a result of the inertia imparted to the plunger hv shoelis ineideiit to the feeding of the primer to its seatJ in the mushroom stein or to the tiring ot' the gun and a premature explosion of the primer will follow. lt' this lange has more than the requisite thielniess the hlow of the tiring hammer against the plunger will fail to shear the flange ainl a iiiislire of thel gun will result. ln turningl these plungers to shape, it is dillieult to produee the shearing [langes of a unit'orin and requisite thieliness as a sharp eutting tool will result in a shearing flange ot' less than the requisite thieltness while a relatively dull tool will produite a shearing Ilange having too great :i thieltness to permit the eoireet operation of the primer, and in many instanees a dull tool will also rupture or partly shear the flange during turning.

It, is theiel'oro my purpose to provide a primer plunger einhod'ving an improved ronstruction wherehy the deleets and ohjertions previously noted ai'eI oliviated. 'l`o this end l form the shearing nieniher iiidepeudentl)Y ofthe hody ot' the plunger and then assenihlo saine. therewith. By so i-,onstrueting the shearing nieniher i ani eiiahled to utilizel sueh method or methods ol' nianulaeture as will assure the requisite thieliness thereof necessary to the safety and eoireet opera tion ot. the primer.

ln the, drawings ehosen l'oil the purpose ol illustrating mi' invention7 the scopo whereof is pointed out in the elaims; Figure l isa longitudinal section through a primer einhodvmg a plunger eoiistrueted in aeeordani-e with inv invention: Fig, L. a longitudi` and Fig. 5. a sei-tion on the line 3 of il* ig. t. I

ln the drawings is the primer ease whieh is ot tuhuhir t'orm and has \one end ot' its hoie redueed as at 10 to form a shoulder l1. 'l`hreaded in the Oase is a plunger eup l whieh ahuts the shoulder l1 and has seated therein a pereussion eap t.

'l`he improved plunger is indieated at l) and is shown as eoniprisiug seetions 1'. and lit. One end of the seetion l2 is engaged in the redueed hoi-e lo wherehv the.phinger ma)Y he sti'uelt h v the tiring hammer ofthe gun for the purpose ot exploding the primer all in the usual and well known manner. 'lhe other end' ot' the seetion l2 is provided with a reeess ll in whieh is fitted a reduced portioir l?) ot' the sei-tion 13. The plunger l) earl-ies :i shearing nieniher lt preferably iu the form ot' a washer. In assenihling thel shearing nieniher is engaged over the i'edueed portion l5 and the latter then fitted in the reeess ll when the member 1t will he elamped hetween theI seetions 1'2 and l. lt will he noted that the reduced poi'- tioii lf ot the iiienihei' lil is slightly longer than the depth of the reeess ll so that when the seetious 1; and ll are iiiterfitteil a eii'- euniserihing groove is'formed in whieh the nieniher 1t? seats. 'l`he interior of tho plunger eup is provided with a shoulder li' whieh is engaged h v the member lli w'hereh' the plunger is iiorniallv held out ot' engageiiienl with the rap \\'hen the plunger l) is sti-nek hv the hammer of the firingr nieeha'nism ot' the gun the ineinher 1G is slieared and the phiiiger driven into engageA nient. with the eap C to explode the. primer.

lii the modified form ot'- my invention illustrated in Figs. l and 5 V provide the, plunger with a eireumserihing groove 1S wherein is liited a shearing nieniher lil. This nieniher l!) is in the l'oi'iii of a spiit washer and is l'oreed over the. plunger at the groove 1S until the nieniher is disposed eoneeiitrie with the. plunger when the ends ofthe member will slightly contract to secure same in proper assembled relation.

I preferably form the shearing members 16 and 19 by stamping or pressing although any other method of manufacture may be employed that will assure the requisite thickness thereof essential to the safety and correct operation of the primer. By making the shearing members fromrolled sheets, a homogeneous material is used and consequently uniform shearing resistance is assured.

Vhat I claim and desire to secure by Letters Patent is:

A primer eomprisin erasing, a plunger cup therein provide with an lnterlor shoulder, a percussion cap in said cup, a plunger, and a shearing member formed independently of and carried by the plunger and normally engaging said shoulder to hold the plunger against firing-movement With respect to the cap.

In testimony whereof, I aiix my signature, in the presence of two witnesses.

DORSEY FROST ASBURY.

Witnesses:

C. G. EVANS, A. Y. LEECH, r. 

